Color choices can make or break a good sign. When choosing colors for your yard signs, keep the '40 feet away at 40 miles an hour' rule in mind. Keep the color contrast high: black and white, black and yellow, white text on intense colored backgrounds, black or intense colors on white backgrounds. As a rule, white text on an intensely colored background, such as white on bright red, can 'sparkle' and be more readable than two equally bold colors, such as bright blue on bright red, which only fight for your eye's attention.